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Microscopic experimental study on the effects of NaCl concentration on the self-preservation effect of methane hydrates under 268.15 K

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Chinese Journal of Chemical Engineering 2024年第9期73卷 1-14页

作者： yu-Jie Zhu yu-zhou chen Yan Xie Jin-Rong Zhong Xiao-Hui Wang Peng Xiao Yi-Fei Sun Chang-yu Sun Guang-Jin chen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Research Centre of Ecology&Environment for Coastal Area and Deep Sea Guangdong University of TechnologyGuangzhou 510006China School of Chemistry and Food Engineering Changsha University of Science and TechnologyChangsha 410114China

It is known that salt ions are abundant in the natural environment where natural gas hydrates are located;thus,it is essential to investigate the self-preservation effect of salt ions on methane *** dissociation behaviors of gas hydrates formed from various NaCl concentration solutions in a quartz sand system at 268.15 K were investigated to reveal the microscopic mechanism of the self-preservation effect under different salt *** showed that as the salt concentration rises,the initial rate of hydrate decomposition *** hydrate hardly shows self-preservation ability in the 3.35%(mass)NaCl and seawater systems at 268.15 *** the morphology of hydrate observed by the confocal microscope with results obtained from in situ Raman spectroscopy,it was found that during the initial decomposition stage of gas hydrate below the ice point,gas hydrate firstly converts into liquid water and gas molecules,then turns from water to solid ice rather than directly transforming into solid ice and gas *** presence of salt ions interferes with the ability of liquid water to condense into solid *** results of this study provide an important guide for the mechanism and application of the self-preservation effect on the storage and transport of gas and the exploitation of natural gas hydrates.

关键词： Gas hydrate Self-preservation Salinity In situ Raman spectroscopy Endothermic behavior Dissociation

One new bufadienolide biotransformed from cinobufagin by Cunninghamella elegans

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Chinese Chemical Letters 2008年第3期19卷 299-301页

作者： Li Qiao yu Zhi zhou Huan chen Jia Qing Cao yue Hu Pei School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China

Cunninghamella elegans has been employed for the biotransformation of cinobufagin （1） to afford one metabolites. The structure of the transformation product has been characterized as 7β,12β-dihydroxylcinobufagin （2）. Product 2 is a new compound. In vitro cytotoxic activities of the biotransformation product and the substrate-cinobufagin have been assayed against HeLa; they all showed cytotoxic activities.

关键词： Biotransformation Cinobufagin 7β,12β-Dihydroxylcinobufagin Cunninghamella elegans

Co/Co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang chen Yongyue Zhuang Yanxin Qiao yu Zhang Aihua yuan Hu zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NCS)decorated with dual-phase Co/Co_(7)Fe_(3)heterojunctions(CoFe@NCS).The phase composition of materials has been adjusted by controlling the alloying *** optimal CoFe_(0.08)@NCS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active Co_(7)Fe_(3)alloy and metallic Co *** the CoFe_(0.08)@NCS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/C+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

A hiddenly high hepatitis C virus related liver disease burden among Chinese patients with non-liver disease complaints: A hospital based study from 2013 to 2017

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Asian Pacific Journal of Tropical Medicine 2018年第2期11卷 171-176页

作者： Hua-Ping Huang Guo-Sheng yuan yu-chen zhou cheng-Guang Hu Jun-Wei Liu Shuai yuan yu-Rong Qiu Yi-Ping Li Yong-yuan Zhang yuan-Ping zhou Department of Infectious Diseases and Hepatology Unit Nanfang HospitalSouthern Medical University Department of Respiratory Diseases The First Affiliated Hospital of Hainan Medical University Department of Hepatobiliary Surgery Nanfang HospitalSouthern Medical University Laboratory Medicine Center Nanfang HospitalSouthern Medical University Institute of Human Virology and Key Laboratory of Tropical Disease Control of Ministry of Education Zhongshan School of MedicineSun Yat-sen University HBVtech

Objective: To determine the frequency of anti-HCV antibody positivity in patients with nonliver disease complaints, to explore whether anti-HCV positive patients had been properly advised and visited hepatologists for further assessments, and to investigate their clinical characteristics as well as the HCV treatment ***: A hospital based survey of nonliver disease patients with anti-HCV positive and their attending physicians was conducted to determine: *** the patients adequately advised of the implication of anti-HCV positive finding; *** what extent the patients were aware of potential chronic liver disease associated with HCV infection and whether they sought for further assessments and care of ***: A total of 295 294 non-liver disease patients were tested for anti-HCV antibody, and 2 778 of them were found to be positive(0.94%).However, only 45.10%(1 253/2 778) of the anti-HCV antibody(+) patients were referred to hepatologists and received HCV RNA *** addition, 34.10%(312/915) and 1.42%(13/915) of them had already advanced to cirrhosis and hepatocellular carcinoma(HCC), *** analysis showed that the patients who declined antiviral therapy were older, with lower education and lower income, possessed poorer knowledge on the risk of chronic hepatitis C, and had more severe liver ***, 65% of the surveyed physicians did not know the genotype-guided treatment duration suggested by the ***, 22% of the surveyed physicians did not know the standard assays for the diagnosis of HCV ***: Our findings highlight the challenge and hidden enormous burden of chronic HCV infection among patients with non-liver disease complaints in China.

关键词： China HCV Hepatitis C antibody Diagnosis Treatment status Survey

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO_(2)

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing chen Chao Wu Xiaoling Liu Biao Meng Tao chen yu Han Jun Wang Shibo Xi yu zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816JiangsuChina Advanced Membranes and Porous Materials Center Physical Sciences and Engineering DivisionKing Abdullah University of Science and TechnologyThuwal 23955-6900Saudi Arabia Institute of Sustainability for Chemicals Energy and EnvironmentA*STAR(Agency for ScienceTechnology and Research)Jurong IslandSingapore 627833Singapore College of Materials Science and Engineering Sichuan UniversityChengdu 610065SichuanChina

The synergy of single atoms(SAs)and nanoparticles(NPs)has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction(CO_(2)RR);however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly(ionic liquids)(PIL)precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO_(2)into *** Ni K-edge X-ray absorption near-edge structure(XANES)spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO_(2),the coexistence of Ni SAs and NPs strengthened the CO_(2)activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO_(2)→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Single atom catalyst Synergy effect cO2 reduction Carbon catalyst Electrocatalysis

Architecture and key technologies of grid geographic information system

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Science China(Technological Sciences) 2008年第S1期51卷 102-113页

作者： FANG yu,HUANG zhou,chen Bin,WU Lun & YIN DaFei Institute of Remote Sensing and Geographic Information System,Peking University,Beijing 100871,China Institute of Remote Sensing and Geographic Information System Peking University Beijing 100871 China

The highly efficient and stable collaborative computation platform for geospatial information can be constructed on the basis of Grid computing technology,com-bined with Peer-to-Peer (P2P) computing technology and geospatial database technology. This paper proposed the architecture and key technologies of the Grid GIS (Geographic Information System) incorporated with P2P structure,and corre-spondingly a Grid GIS prototype named Nebula was designed and then imple-mented. Nebula is a suite of middleware for geospatial Grid computing,which could be deployed onto various service nodes in network. Based on Grid protocols and infrastructure,Nebula provides invocation interfaces to users in form of Grid services. By using P2P message based communication mechanism,complex geospatial computation tasks could be accomplished by Nebula in a collaborative way. This paper introduced Nebula's architecture and key modules,and according to experimental data,we discussed the Grid GIS's advantages,application scenar-ios and future directions.

关键词： Grid GIS distributed geospatial computing Peer-to-Peer computing

A sampling method based on URL clustering for fast web accessibility evaluation

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Frontiers of Information Technology & Electronic Engineering 2015年第6期16卷 449-456页

作者： Meng-ni ZHANG Can WANG Jia-jun BU Zhi yu yu zhou Chun chen College of Computer Science and Technology Zhejiang University Hangzhou 310027 China

When evaluating the accessibility of a large website, we rely on sampling methods to reduce the cost of evaluation. This may lead to a biased evaluation when the distribution of checkpoint violations in a website is skewed and the selected samples do not provide a good representation of the entire website. To improve sampling quality, stratified sampling methods first cluster web pages in a site and then draw samples from each cluster. In existing stratified sampling methods, however, all the pages in a website need to be analyzed for clustering, causing huge I/O and computation costs. To address this issue, we propose a novel page sampling method based on URL clustering for web accessibility evaluation, namely URLSamp. Using only the URL information for stratified page sampling, URLSamp can efficiently scale to large websites. Meanwhile, by exploiting similarities in URL patterns, URLSamp cluster pages by their generating scripts and can thus effectively detect accessibility problems from web page templates. We use a data set of 45 web sites to validate our method. Experimental results show that our URLSamp method is both effective and efficient for web accessibility evaluation.

关键词： Page sampling URL clustering Web accessibility evaluation

A Novel Self-Supervised Learning Network for Binocular Disparity Estimation

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 209-229页

作者： Jiawei Tian yu zhou Xiaobing chen Salman A.AlQahtani Hongrong chen Bo Yang Siyu Lu Wenfeng Zheng Department of Computer Science and Engineering Major in Bio Artificial IntelligenceHanyang UniversityAnsan-si15577Republic of Korea School of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA 70803USA Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh11574Saudi Arabia School of Automation University of Electronic Science and Technology of ChinaChengdu610054China

Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical *** study proposes a novel end-to-end disparity estimation model to address these *** approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting *** study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and *** model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video *** results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing ***,the model exhibited faster convergence during training,contributing to overall performance *** study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments.

关键词： Parallax estimation parallax regression model self-supervised learning Pseudo-Siamese neural network pyramid dilated convolution binocular disparity estimation

Traditional Chinese medicine in the treatment of Helicobacter pylorirelated gastritis:The mechanisms of signalling pathway regulations

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World Journal of Gastroenterology 2025年第3期31卷 11-28页

作者： Pei-Pei Zhang Liang Li Hao-yu Qu Guang-yu chen Meng-zhou Xie Yan-Kun chen School of Traditional Chinese Medicine Hunan University of Chinese MedicineChangsha 410200Hunan ProvinceChina Hunan Engineering Technology Research Center for Medicinal and Functional Food Hunan University of Chinese MedicineChangsha 410200Hunan ProvinceChina Key Laboratory of Traditional Chinese Medicine Heart and Lung Syndrome Differentiation and Medicated Diet and Dietotherapy Hunan University of Chinese MedicineChangsha 410200Hunan ProvinceChina School of Informatics Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Precision Medicine Research and Development Center Zhuhai Institute of Advanced TechnologyChinese Academy of SciencesZhuhai 519000Guangdong ProvinceChina

Helicobacter pylori-associated gastritis(HPAG)is a common condition of the gastrointestinal ***,extensive and long-term antibiotic use has resulted in numerous adverse effects,including increased resistance,gastrointestinal dysfunction,and increased recurrence *** these concerns develop,traditional Chinese medicine(TCM)may have *** is based on the concept of completeness and aims to eliminate pathogens and strengthen the *** has the potential to prevent this condition while also boosting the rate of Helicobacter pylori *** review elaborates on the mechanism of TCM treatment for HPAG based on cellular signalling pathways,which reflects the flexibility of TCM in treating diseases and the advantages of multi-level,multipathway,and multi-target treatments for HPAG.

关键词： Helicobacter pylori Helicobacter pylori-associated gastritis Traditional Chinese medicine Signalling pathway Eliminate pathogens Strengthen the body